奶牛两种菌型乳房炎易感性多座位基因型的筛选和验证的研究

课题组既有研究发现IL8及其受体CXCR1在奶牛乳房炎免疫调控信号通道中扮演重要角色，SNP扫描和多座位聚合统计分析表明以上两基因3个变异位点的多座位基因型AG/TA/KA具最高的MSE值。在此基础上，本研究1、通过奶牛乳房内S. agalactiae和S. aureus攻毒试验、芯片杂交、信号通路分析和差异蛋白质液相色谱-电喷雾串联质谱联用分析，筛查奶牛乳房炎主要免疫信息通道和易感性相关分子标记、候选基因；2、对信号通路上主要基因外显子和调控序列进行群体SNP扫描，并进行群体遗传学分析；3、通过构建多座位降维离差分析模型，进行多座位聚合分析，筛选出奶牛两种菌型乳房炎易感性多基因组合和易感性多座位基因型；4、对筛选出的多座位基因型进行细胞学和活体验证。该研究为研明奶牛乳房炎免疫调控机制和奶牛乳房炎易感性多座位标记辅助选择奠定基础。

The recent researches of our research group revealed the important role of IL8 and its receptor CXCR1 in the immune regulatory pathway against mastitis in dairy cow. SNP screen and multi-loci combination statistic analysis indicated the highest MSE value occurred in the genotype AG/TA/KA at three mutation sites. Based on these results, this research will conduct a series of experiments and analyses including S. agalactiae and S. aureus challenge test in mammary gland, gene chip hybridization, signaling pathway analysis and LC-ESI-MS/MS, to screen main immune signal and related molecular markers.The study will also screen for SNPs in the main exons and regulatory region and conduct multi-loci combination statistic analysis using Multi-loci Reducing Dimensionality and Daviation model aiming to screen for S. agalactiae and S.aureus susceptible gene combination and multi-loci genotypes with cellular and in vivo verification. The findings would pave a sound foundation for clarifying the mechanism of immunoregulation and multi-loci marker-assisted selection against S.aureus causing mastitis in dairy cow.